Fluidizer and dispenser

ABSTRACT

The fluidizer and dispenser has a storage container mounted above the fluidizing chamber and a valve system to meter small increments of pulverant material from the storage container to the fluidizing chamber. The fluidizing element comprises a cylinder having an air nozzle and fluidizing plate and a diffuser plate extending across its lower area to provide a fluidized bed of pulverant material in the region above the plate. Part of the fluidized bed of pulverant material is aspirated by means of the jet into a conduit through which it is conducted in air solution. Fluidized pulverant material is conducted to a nozzle and there sprayed onto a can or other surface.

United States Patent [72] Inventors Boris J. Kirsanolf Glenwood; Joseph J. Merle; Robert A. Winkless, Oak Lawn, Ill. [21] Appl. No. 772,988 [22] Filed Nov. 4,1968 [45] Patented Mar. 16, 1971 [73] Assignee Continental Can Company, Inc.

New York, NY,

[54] FLUIDIZER AND DISPENSER 5 Claims, 7 Drawing Figs.

[52] U.S. Cl 222/67, 222/193, 222/450 [51] Int. Cl 865g 3/12 [50] Field of Search 222/ 193, 195, 67,444, 450, 529; 137/268, (Inquired) [56] References Cited UNITED STATES PATENTS 1,390,974 9/1921 VonPorat 222/195X 2,167,416 7/1939 Carlson 222/195 Primary Examiner-Robert B. Reeves Assistant Examiner-David A. Scherbel Attorneys-Americus Mitchell, Joseph E. Kerwin and William A. Dittmann ABSTRACT: The fluidizer and dispenser has a storage container mounted above the fluidizing chamber and a valve system to meter small increments of pulverant material from the storage container to the fluidizing chamber. The fluidizing element comprises a cylinder having an air nozzle and fluidizing plate and a diffuser plate extending across its lower area to provide a fluidized bed of pulverant material in the region above the plate. Part of the fluidized bed of pulverant material is aspirated by means of the jet into a conduit through which it is conducted in air solution. Fluidized pulverant material is conducted to a nozzle and there sprayed onto a can or other surface.

PATENTEU HAM 6 new SHEEY 1 BF 3 INVENTORS ore/s J. KIRSA NOFF JOSEPH J. MERLE ROBERT A. WINKLESS ATT Y.

PATENTED m1 6 |97| 'SHEET 2 OF 3 INVENTORS BORIS J KIRSANOFF JOSEPH J MERLE ROBERTA. WINKLESS SOURCE FLUIDIZER AND DRSPENSER Our invention relates to a method and means for luidizing pulverant materials and specifically fluidizing polymer resin powders to be used for coating side seam areas of formed metal containers.

This apparatus is an improvement of Pat. application Ser. No. 669,897 entitled Powder Dispensing Device by Ernest W. Dewitt et al., filed Sept. 22, 1967, and assigned to the assignee of this invention.

Our invention relates to the field of coating when a spray nozzle, for example, is utilized to deposit a film of coating material upon an article. This type of apparatus is used, particularly in coating side stripe seams of cans or containers for the purpose of providing protection for the seam area and to heighten the aesthetic appeal of the finished container.

It is an object of the present invention to provide a finely divided fluidized powder which may be conveyed by a gaseous transport medium from a fluidizer to a dispensing nozzle.

It is another object of this invention to provide a means for fluidizing a pulverant powder to give an aspirator bed of nearly uniform consistency to aid in level control.

It is another object of this invention to provide a means for feeding a fluidizer bed to maintainit at approximately a constant level. 4

FIG. 1 is a perspective view of the powder dispenser and fluidizer.

FIG. 2 is a side elevation of the fluidizing bed of the dispenser.

FIGS. 3, 4 and 5 are enlarged sectional views taken along Line 3-3 of FIG. 2 and show a variety of exit port structures for varying the powder outlet passageway.

FIG. 6 shows the structure of the fluidizer and porous diffuser plate.

FIG. 7 shows an enlarged fragmentary sectional view taken along the Line 7-7 of FIG. 2 showing the cap member and feed tube.

Referring now to FIG. 1, the view shown has at its upper position a fluidizing storage container 1 for pulverant powder. This storage container has a dispensing orifice at its lower end. Attached to the dispensing orifice is a hollow feed tube 2 having a central section 3 of some elastomeric material, such as rubber, so that an air lock may be fom formed in this tube. Two spaced valves 4, 5 are mounted adjacent the elastomeric tube and adapted to be operated independently of each other, one valve 4 above the other valve 5. The valving action is accomplished by applying a constrictor to the rubber hose. The constriction may be applied by piston, pneumatic pressure, or any other quickly responsive means to close the sides of the tube together and restrict the flow of material past the point where valving is to take place. Attached to the bottom of the hollow feed tube is the cylindrical powder dispensing device 6 and fluidizer bed. A small bleed line 7 is connected between the upper part of the hollow feed tube and the top of the storage container. This tube equalizes air pressure between the feed tube and storage container to prevent air lock. The operation of this device is essentially as follows:

The fluidizing storage container 1 is filled up from time to time with the pulverant powder to be used. This powder is fluidized and is allowed to pass through a check valve in th the bottom of the storage container and down to the upper air lock valve 4. The container check valve, the upper airlock 4, and the lower air lock valve 6 are all synchronized in the following way:

A high-low fluid level sensing means 8 is mounted so as to respond to appropriate levels of fluid in the fluidized powder dispenser. A float 12 in the cylindrical powder chamber rests on top of the fluidized powder in the fluidizer in the same manner as a float operates on the top surface of a liquid. When the level of fluidized material in the dispenser reaches a predetermined low point, then the fluid level sensing means actuates a switch 9 to open the container check valve located inside the container. The check valve allows a certain amount of fluidized powdered resin to fall past the open upper air lock valve 4 and come to rest against the lower air lock valve 5. The

upper air lock valve 4 then closes and a moment later, the lower air lock valve 5 opens to allow the measured amount of material to fall into the powder dispensing and fluidizing device. Little or no pressurized fluid escapes from the fluidizing device through the air locks. The cycle is repeated until, by the addition of successive small increments, the level of the fluid in the fluidizing device reaches the upper signal level of the high-low float. Switch 10 is then closed and a mechanism 11 so stops operation of the air lock valves. In brief, when the fluidized powder comes to a predetermined low level, the float 12 operates a switch to start the cycling indicated above. The fluidized powder is filled to some predetermined high level, and at this point, the float switch 10 operates to cause the powder feed from the storage container to cease.

As an alternative, the upper air lock valve may be omitted, and the powder from the container comes to rest initially against the container check valve. The container check valve opens briefly to allow the passage of a small amount of powder past it to the closed lower air lock valve. After the container check valve has closed, the lower air lock valve opens to allow the powder in the elastomeric tube to flow into the fluidizer. The fluidized powder remains in the air lock very briefly and stays in a fluid condition I Dry air or some other gas is introduced into the lower chamber of the cylindrical powder dispensing device andpasses under pressure through a porous block 13 up to the upper chamber of the cylindrical powder dispensing device. The gas is forced into the upper chamber, disperses and buoys up the powder. In this manner, the fluidized powder is uniformly dispersed throughout the chamber of the cylindrical powder dispensing device and is aspirated out of the device and carried along in the gaseous transfer medium to a nozzle. A high-frequency vibrator vibrates the dispensing device to help keep the powder in fluidized condition. As the powder jets out of the nozzle, it is applied to a can seam or used in some other application. I,

Details of the cylindrical powder dispensing and fluidizing device are shown in FIG. 2. In this embodiment, a large porous diffuser block 13 is shown which is coextensive with the sides of the cylindrical powder dispensing device. In this way, as the air under pressure from below diffuses through the block 13 and passes into the fluidized pulverant material 14, a fluidized bed of pulverant material coextensive with the walls of the cylindrical dispensing device is created and maintained so long as a supply of air is fed through the diffuser block. Since the entire charge of the dispenser is in the fluidized condition, solid inclusions do not build up to clog the smaller openings of the device.

The aspirator operates in the following way:

Air under pressure is conducted up through the aspirator tube 15 to jet forth in the direction of the hollow feed tube 16. As the jet of air passes through the fluidized bed, some particles of the resin powder are aspirated into the jet of air and are carried in fluidized form to the hollow feed tube 16 to exit from the cylindrical powder dispensing device through the top wall 17 of the chamber. The fluidized pulverant material becomes intimately mixed with the air or other vehicle passing through the aspirator tube 15 and out of the cylindrical powder dispensing device to the point that a fluid solution is formed and is passed for further processing.

A variety of connections at the top of the cylindrical powder dispensing device are possible and are shown in FIGS. 3, 4 and In these modifications, the fluid solutions is jetting out of a hollow feed tube 16 and into the exit conduit 18. The modification of FIG. 3 shows a hollow feed tube 16 which conducts the air and aspirated fluidized powder out of the chamber. The fluid introduced into the chamber through the porous block 13 passes out of the chamber and into tube 36 through ports 19 located at the top of the tube near upper wall 17. The additional fluid gives more volume and flow to the fluid vehicle thus lowering the possibility of clogging in the tube 16 and conduit 18.

FIG. 4 shows a modification wherein the upper wall 17 of the dispensing device has a lip 21 around the exit tube area so that any pulverant material which might spill over in the transfer from the hollow feed tube to the exit conduit does not tend to clog and agglutinate around the entrance to the exit tube 18, but rather is swept back into the mass of fluidized pulverant material by air currents. In this way, clogging of the exit port is avoided.

FIG. 5 shows the hollow feed tube 16 and exit conduit 18 as integral and extending through the upper wall of the cylindrical powder device. In this embodiment, an additional exit conduit (not shown) removes the pressurized fiuidizing air from the dispenser. Pressure inside the dispenser chamber is maintained constant by a back pressure regulator or the like in the additional exit conduit.

The details of the fluidizer, diffuser block, hollow aspirator needle, and air cylinder on-off switch means 22 are shown most clearly in FIG. 6. Air under pressure is admitted into the bottom of the compartment and passes upward through the porous diffuser plate 13. The area beneath the block is under pressure and the air diffuses through the porous block to pass upward through the entire' mass of pulverant material and bring it to a fluidized condition throughout as the pressurized air passes more or less equally through all parts of the pulverant material. Since the pressurized air passes equally through all parts of the pulverant material, there are no lumps or clots in the fluidized material, and there is little or no chance that this material will clog up the outlet tube 18. The use of the vibrator aids this effect. As explained above, the aspirator tube extends through the porous block 13 to jet air and aspirated powder up through the hollow feed tube. The gap between the aspirator tube and the hollow feed tube is adjusted by an air cylinder 22 located below the fluidizer chamber 6. The piston of the air cylinder is attached to the aspirator tube so that the aspirator tube may be slid into coaptation with the feed tube 16 to purge the feed lines of powder by air current or moved away from the feed tube to aspirate fluidized powder through the feed lines.

Details of construction of the feed tube-exit conduit connection of FIG. 3 are shown in FIG. 7 in which the air-powder mix is jetted out of the feed tube 16 and passes rapidly into the exit conduit 18. Air which has passed through the fluidized powder vents through the exit conduit at ports 19. In this embodiment, the hollow feed tube 16 is made of nylon and extends the entire length of the dispenser and through the top of the dispenser. A metal support tube 23 surrounds the nylon tube and ports 19 are cut into the nylon tube to allow passage of the fluidizing air out of dispenser 6.

Removal of supporting plug 24 and the feed tube assembly from the dispenser is accomplished by loosening screws 25. The tube 16 and its supporting elements 23,26 may be removed by loosening threaded collar nuts 27,28. In this way, feed tube 16 may be replaced without disassembly of the entire apparatus. The feed tube may be adjusted up and down somewhat while the collar cuts are loose.

The foregoing is a description of an illustrative embodiment of the invention, and it is applicants intention in the appended claims to cover all forms which fall within the scope of the invention.

We claim:

1. A powder dispensing device comprising:

a chamber for storing a quantity of powder particles and having substantially smooth lateral walls;

a porous block mounted adjacent the lowermost end of said chamber and extending coextensive with the walls of said chamber;

an aspirator tube means having a constriction in its nozzle end, mounted in the bottom of said chamber and extending through said porous block;

a hollow feed tube having one end located near the other end of said aspirator tube means and extending to the proximity of the top wall of said container;

means for supplying a pressurized flow of gas to said aspirator tube;

means for supplying a pressurized flow of gas to the space between the porous block and the lowermost end of said chamber;

an exit port in said chamber in alignment with said hollow feed tube whereby gas jetting through said aspirator tube carries powder entrained in the gas through said feed tube and out of said exit port;

said exit port a having a protruberance into the chamber about its edge; and

the walls of said one end of said hollow feed tube are beveled externally whereby air currents sweep over said protruberance to keep the area of said protruberance free of powder.

2. A powder dispensing and fluidizing device comprising:

a pressurized chamber;

means for fluidizing powder in said pressurized chamber;

means for conducting said fluidized powder out of said pressurized chamber;

a feed port in the top wall of said chamber;

an unpressurized powder storage container mounted above said chamber and having an outlet port in its lower end and an outlet spout connected to said outlet port;

a bypass tube connected between said outlet spout and the upper portion of said storage container whereby air pressure between said spout and the space above said powder is equalized to allow flow of powder out of said container through said spout;

an elastomeric hose connected between said spout and said port in the upper wall of said pressurized chamber;

first and second pinch means attached to said hose at spaced points for pinching the sides of said hose closed;

actuating means attached to said pinch means to open and close said pinch means in an alternating sequence whereby at least one of said pinch means is closed on said tube at any given instant to allow the movement of powder through said hose from said unpressurized powder storage container to said pressurized chamber.

3. A powder dispensing and tluidizing device as set forth in claim 2 having additionally; a particle level sensor for sensing the level of particles in said pressurized chamber and for starting said actuating means when the level of said fluidized particles fall below a predetermined level and stopping said actuating means when said level rises to another predetermined level.

4. A powder dispensing device comprising:

a chamber for storing a quantity of powder particles and having substantially smooth lateral walls;

a porous block mounted adjacent the bottom wall of said chamber and extending to the lateral walls of said chamber;

aspirator tube means mounted in the bottom wall of said chamber and having one end thereof extending out of said chamber and the other end extending through said porous block;

means for supplying a pressurized flow of fluid to the space between the porous block and the lowermost end of said chamber;

a plastic hollow feed tube having one end located near said other end of said aspirator tube means and extending through the top wall of said chamber;

slots in the tube wall of said hollow feed tube and located near the top wall of said dispenser;

a metal support tube surrounding said hollow feed tube and connected to said top wall and having vent sections found in said metal support tube which vent sections lie over the slots in said tube wall whereby pressurized fluid passing through said aspirator tube and pressurized fluid in the space between the upper surface of said fluidized particles and the top wall of said chamber passes continually through said hollow feed tube.

5. A powder dispensing device comprising:

a chamber for storing a quantity of powder particles and having substantially smooth lateral walls;

a porous block mounted adjacent the bottom wall of said chamber and extending to the lateral walls of said chamber;

aspirator tube means mounted in the bottom wall of said chamber and having one end thereof extending out of 5 said hollow feed tube having slots in the tube wall and located near the top a wall of said dispenser;

a feed port in the top wall of said chamber;

a powder storage container mounted above said chamber and having an outlet port in its lower end and an outlet spout connected to outlet port;

a bypass tube connected to allow fluid to pass between said spout and the upper portion of said storage container whereby air pressure is equalized to allow flow of power out of said container;

an elastomeric base connected between said spout and said feed port; and

air lock means for pinching said hose closed or allowing said hose to open. 

2. A powder dispensing and fluidizing device comprising: a pressurized chamber; means for fluidizing powder in said pressurized chamber; means for conducting said fluidized powder out of said pressurized chamber; a feed port in the top wall of said chamber; an unpressurized powder storage container mounted above said chamber and having an outlet port in its lower end and an outlet spout connected to said outlet port; a bypass tube connected between said outlet spout and the upper portion of said storage container whereby air pressure between said spout and the space above said powder is equalized to allow flow of powder out of said container through said spout; an elastomeric hose connected between said spout and said port in the upper wall of said pressurized chamber; first and second pinch means attached to said hose at spaced points for pinching the sides of said hose closed; actuating means attached to said pinch means to open and close said pinch means in an alternating sequence whereby at least one of said pinch means is closed on said tube at any given instant to allow the movement of powder through said hose from said unpressurized powder storage container to said pressurized chamber.
 3. A powder dispensing and fluidizing device as set forth in claim 2 having additionally; a particle level sensor for sensing the level of particles in said pressurized chamber and for starting said actuating meaNs when the level of said fluidized particles fall below a predetermined level and stopping said actuating means when said level rises to another predetermined level.
 4. A powder dispensing device comprising: a chamber for storing a quantity of powder particles and having substantially smooth lateral walls; a porous block mounted adjacent the bottom wall of said chamber and extending to the lateral walls of said chamber; aspirator tube means mounted in the bottom wall of said chamber and having one end thereof extending out of said chamber and the other end extending through said porous block; means for supplying a pressurized flow of fluid to the space between the porous block and the lowermost end of said chamber; a plastic hollow feed tube having one end located near said other end of said aspirator tube means and extending through the top wall of said chamber; slots in the tube wall of said hollow feed tube and located near the top wall of said dispenser; a metal support tube surrounding said hollow feed tube and connected to said top wall and having vent sections found in said metal support tube which vent sections lie over the slots in said tube wall whereby pressurized fluid passing through said aspirator tube and pressurized fluid in the space between the upper surface of said fluidized particles and the top wall of said chamber passes continually through said hollow feed tube.
 5. A powder dispensing device comprising: a chamber for storing a quantity of powder particles and having substantially smooth lateral walls; a porous block mounted adjacent the bottom wall of said chamber and extending to the lateral walls of said chamber; aspirator tube means mounted in the bottom wall of said chamber and having one end thereof extending out of said chamber and the other end extending through said porous block; means for supplying a pressurized flow of fluid to said aspirator tube; means for supplying a pressurized flow of fluid to the space between the porous block and the lowermost end of said chamber; a hollow feed tube having one end located near said other end of said aspirator tube means and extending through the top wall of said chamber; said hollow feed tube having slots in the tube wall and located near the top a wall of said dispenser; a feed port in the top wall of said chamber; a powder storage container mounted above said chamber and having an outlet port in its lower end and an outlet spout connected to outlet port; a bypass tube connected to allow fluid to pass between said spout and the upper portion of said storage container whereby air pressure is equalized to allow flow of power out of said container; an elastomeric base connected between said spout and said feed port; and air lock means for pinching said hose closed or allowing said hose to open. 